don't speak unless you know what you are talking about, i've ran 87 in mine since i bought it 2 and a half years ago

 

if you have 215lbs compression then I say leave it alone!! that is a very good # for a stock piston , so you have no issues with rings and such. do the end cap,and gearing,and you'll be happy. and when your ready for more aggressive pull then go with some cams.



Bigger.

 

well vision i have read every post since day one and mr hp i think says to run 87 octane to advance the timing that is why i do it, i wanna freshen up my motor jjst for something to do, im not gonna get cams or bigger carbs just a ported intake and endcap with probably a cdi box, i think i am also gonna have a valve job done when i get the head ripped off, just my two cents, i could go all out iwht a big bore kit two carbs etc but why the slightly modded ds has more than enough power for me, im 37 with a bad back lol

 

The lowest the octane of fuel that you can run without pre-ignition will result in more power. Octane is pretty much a measure of resistance to ignition. I used to always run 87 in mine, and told my friends it not a performance machine I dont need premium. I just didint feel like aguing with what their friend's dad's brother's friend had told them about making all this hp on 114 race gas.
Justin

 

Sandman, I've tried PMing you 4 times and no reply, ???
Jackass, I guess I'd be one of those guys beating stage 2s with a stock bike[img]i/expressions/face-icon-small-smile.gif[/img] Gearing and tire choice are #1 Your motor doesn't sound like it needs to be opened up. The encap is a great idea along but make sure you jet properly and your trails don't require a spark arrestor or decibel limits.
If you take off your carb and look down the intake you will most likely see it's mismatched to the head, if you get it lined up that's worth 85% of the gains a ported intake will get you.
Check your exhaust gaskets, if they stick into the exhaust flow trim them.
Big, light tires that really hook up and use the lowest gearing that will still hit the top speed you need.
40% springs will be plenty strong enough.

 

I agree with bigger if your compression numbers are good - leave it alone. It'll cost about $100 to replace the head gasket and rings and there are better ways to spend the $ if your motor tells you it's sealing up just fine now.

 

i just wanna pull the head off and check my ring gap and maybe a valve job then ported intake how long does it take to pull the motor, after i have the tank and seat carbs and everything off, i think there is only like 5 bolts holding it in

 

hey mysteroid do i need a dremel tool or just move the intake around so it lines uo witht he gasket and the head? i am kinda being obsesssive but i wanna make sure the inside of my motor is tip top shape for next yearm im gonn aget the baja fenders nerfs and all

 

im not trying to be an *** or anything major you helped me so much with adjusting my valves i just wanna make sure everything is like new on the inside before i get my froam powdercoated thats all i hope i did not offend you if i did i am sorry, this is gonna be my baby lol

 

Buy a dremel if you don't have one. Do a search on intake porting and you will save enough to buy one. The bolt holes may have to be filed or ground enough to line up the ports but my ports matched perfectly after alignment. Port the rubber intake, it juts into the airflow. Dremel sanding drums work for this. Clamp it to the intake and match that side then clamp ti to the carb and match it there. Mark it so you don't turn it and try to clamp it with the same pressure as when on the quad. More clamping deforms the rubber and pushes it into the airflow. Match the exhaust gaskets to the exhaust ports. They also obstruct airflow.
Save your money, unless you put a gajillion hours on your quad it's most likely in good shape, you can always go through the top end with the motor in the frame later. If you are worried, get a leak down test done.
Bmw chose this motor for it's reliability and then helped redesign the head.